A remote controlled medical instrument for remote controlling an actuator inserted into the body and treating an object in the body includes a polypectomy instrument for resecting the polyp formed in the body, a body tissue collecting instrument for collecting a malignant or benign tissue of the body and an internal foreign object extracting instrument for extracting a foreign object taken inside the body.
The polypectomy instrument, serving by way of example as the above remote controlled medical instrument, conventionally includes a monopolar type and a bipolar type. The monopolar type includes instruments such as that disclosed in Japanese Laid-Open Patent Publication No. 05-337130, and the bipolar type includes instruments such as that disclosed in Japanese Laid-Open Patent Publication No. 10-137261. FIG. 10 is a view showing the above mentioned monopolar polypectomy instrument. In FIG. 10, the polypectomy instrument 50 includes a wire section 51 inserted into the stomach or the intestine through an endoscope, and a remote control section 52 with which the doctors performing the surgery control the wire section 51 outside of the body. H is a high-frequency generator for flowing high-frequency current to the polypectomy instrument 50.
In the wire section 51, 53 refers to a snare serving as an actuator for resecting the polyp P formed at the wall W of the stomach or the intestine (the intestine herein). The snare 53 is an electrode formed by forming a steel stranded wire into a loop shape, and a high-frequency current is flowed out from the high-frequency generator H, as hereinafter described. 54 is a wire made of a steel stranded wire with the snare 53 coupled to the front end, and the rear end of the wire 54 is coupled to the remote control section 52. 55 is a tube through which the wire 54 and the snare 53 pass in a freely entering and exiting manner and is made of a flexible plastic. Here, only the wire 54 is passed through the tube 55, but by pulling the wire 54 in the R direction, the snare 53 is deformed and accommodated inside the tube 55.
In the remote control section 52, 56 is a rod-shaped main body having a hollow inside, and a slit 56a extending in the longitudinal direction L and R of the main body 56 is formed at the side face. A cap 57 for holding the rear end of the tube 55 to the front end of the main body 56 is attached to the front end (L direction side) of the main body 56, and the wire 54 is passed through the cap 57. 58 is an operating member slidably coupled to the main body 56 in the L and R direction, and is formed with finger inserting holes 58a, 58b through which the forefinger and the middle finger are inserted. 59 is a male jack coupled to the operating member 58, and the rear end of the wire 54 is coupled to the root of a terminal 59a at the center. Thus, when the operating member 58 is slide operated in the L and R direction, the wire 54 coupled to the jack 59 is moved in the L and R direction, causing the snare 53 to project out from the inside of the tube 55 or retract inside the tube 55. Further, the jack 59 is fitted with a female jack 60, and is thereby connected to the high-frequency generator H by way of a cable C1. The high-frequency current generated at the high-frequency generator H thereby flows out through the cable C1 and the jacks 60, 59 to the wire 54, and from the wire 54 to the snare 53. M is an external electrode attached to the abdomen or the buttocks of the patient, and is connected to the high-frequency generator H by way of a cable C2. 61 is a pipe coupled to the operating member 58, and is arranged inside the main body 56. The pipe 61 passes the wire 54 therein and leads it to the operating member 58. 62 is a finger holder coupled to the rear end (R direction side) of the main body 56, and is formed with a finger inserting hole 62a through which the thumb is inserted. When the thumb is inserted into the finger inserting hole 62a, and the forefinger and the middle finger are inserted into the finger inserting holes 58a, 58b of the above mentioned operating member 58, the operating member 58 is slide operated in the L and R direction by the forefinger and the middle finger while holding the main body 56.
The steps of resecting the polyp P formed at the wall W of the intestine and the operations of each part in the above polypectomy instrument 50 will now be explained. First, two jacks 59, 60 are fitted together, and the external electrode M is attached to the abdomen or the buttocks of the patient. Next, the wire section 51 is inserted into the intestine of the patient with the endoscope (not shown). Here, the operating member 58 is sled to a position shown with a dotted line, the pipe 61 and the wire 54 are pulled in the R direction, and the snare 53 is retracted inside the tube 55. When the front end of the wire section 51 is inserted to a location where the polyp P is located, the operating member 58 is sled to a position shown with a solid line. The pipe 61 and the wire 54 are thereby pushed in the L direction, causing the snare 53 to project out from the inside of the tube 55, and the projected snare 53 then encircles the base Pa of the polyp P. Here, in FIG. 10, since the projecting direction (U direction herein) of the polyp P and the loop surface of the snare 53 are parallel, even if the snare 53 is moved in the D direction, the snare 53 does not encircle the polyp P, and thus the polyp P is rotated with the entire intestine with respect to the snare 53 by having the patient change the body position to have the projecting direction of the polyp P perpendicular to the loop surface of the snare 53, and the snare 53 then encircles the polyp P.
Further, when a polypectomy instrument 70 equipped with a rotating mechanism part 71 is used as shown in FIG. 11, the snare 53 easily encircles the polyp P without having the patient change the body position. The reference characters of each part shown in FIG. 11 are the same for parts similar to those in FIG. 10. In FIG. 11, the rotating mechanism part 71 is arranged on the middle of the wire section 51, and is configured from a grip 72 gripped by the hand, a supporting pipe 73 rotatably supported at the middle of the grip 72, and a roller 74 fixed to the peripheral surface of the supporting pipe 73. The supporting pipe 73 passes the wire 54 therein and holds the wire 54. Due to such rotating mechanism part 71, by rotating the roller 74 with the axis of the supporting pipe 73 as the rotating center, the supporting pipe 73 and the wire 54 are rotated in the same direction as the roller 74, and the rotational torque of the wire 54 is transmitted to the snare 53, thus rotating the snare 53 in the same direction as the roller 74. Therefore, the snare 53 is rotated with respect to the polyp P without having the patient change the body position to have the projecting direction of the polyp P perpendicular to the loop surface of the snare 53, and the snare 53 then encircles the polyp P. Further, the surgery can be performed without having the patient change the body position, and thus the load on the patient can be removed.
When the snare 53 encircles the polyp P as above, the high-frequency current is flowed out from the high-frequency generator H to the snare 53 through the wire 54. Thus, the high-frequency current is conducted from the base Pa of the polyp P encircled by the snare 53 through the body of the patient and to the external electrode M, and heat generation as well as burning occurs at a portion of the polyp P having the smallest cross sectional area. Subsequently, when the operating member 58 is gradually sled to the R direction, the pipe 61 and the wire 54 are pulled in the R direction, causing the snare 53 to gradually retract inside the tube 55, and thus the base Pa of the polyp P is tightened by the snare 53. Finally, the base Pa of the polyp is burnt off by the burning by the high-frequency current and the tightening force of the snare 53, and the polyp P is resected from the wall W of the intestine.
In the conventional polypectomy instrument 50, 70, the wire section 51 inserted into the body of the patient is discarded after the surgery in view of infection of disease and hygienic problems. However, since the remote control section 52 and the rotating mechanism part 71 are integrally coupled to the wire section 51, the remote control section 52 and the rotating mechanism part 71 not inserted into the body of the patient are also discarded with the wire section 51, and thus the entire instrument 50, 70 is disposable. This is a great waste when using the instrument, and is a factor in the increase of facility cost of hospitals and the like.